Reelectionist Senator Sonny Angara said the Philippine National Police should make it a priority to protect government critics, including the Catholic priests who came forward to reveal that they had been receiving death threats after criticizing President Duterte's war on drugs.

"If anyone should be protected, it should be the critics of the government. This is to show that we are a democracy and we value freedom of speech and expression," Angara said in an interview with CNN Philippines.

Angara was referring to Catholic priests Albert Alejo, Flavie Villanueva and Robert Reyes, who jointly revealed to the public that they had been receiving threatening SMS messages from still unidentified senders.

Two weeks ago, Caloocan Bishop Pablo Virgilio David, one of the clergymen most critical of Duterte's drug war, also confirmed receiving similar threats.

Angara said the death threats against the priests were a "cause for concern."

During a press conference, the three priests suggested that Duterte could be behind the death threats directed at them.

To settle their differences, Angara is proposing a dialogue between the Church and the government.

"I think dialogue will always be welcome. It's not really good to see our top institutions engaging in mudslinging," Angara said. "That has been done before by other presidents, so why not?"